Darklands Puzzle #11

The path is blocked by an iron door. Above the door is carved:
ONE STATUE ALWAYS LIES, ONE SPEAKS ONLY TRUTH AND THE THIRD SPEAKS BOTH TRUTH AND LIES.
MULTIPLE SOLUTIONS ARE POSSIBLE.
TO OPEN THE DOOR, TOUCH THE ONE THAT CANNOT BE HARDGREP.
The three statues seem to have recently been shuffled around. They speak:
Gold says, "I am Tifsyn. Silver is Hardgrep."
Silver says. "True, gold is Tifsyn. However, I myself am Gymer."
Copper says. "Not so. Gold is Gymer."
You touch...
...the gold statue.
...the silver statue.
...the copper statue.

(Source: Darklands cluebook by MicroProse Software)

The cluebook has the hint "If Gold lies, then Silver cannot be the truth-teller." which was quite useful. If Gold lies then he is not Tifsyn and Silver is the intermediate sort of character (hereafter referred to simply as "the intermediate") who tells one truth and one lie, making him Gymer. This then means that Copper is also a "knave", which is not possible in this case, so this possibility can be disregarded entirely.

On the other hand, if Gold is the intermediate, then either:

• Gold is Tifsyn and Silver is not Hardgrep or
• Gold is not Tifsyn and Silver is Hardgrep

I will not make a further examination of whether Gold even can be the intermediate, like I did in the previous instance of considering whether Gold can be the "knave" because it's already clear that Gold can't be Hardgrep in this instance.

The final possibility that Gold is the "knight" leads to the trivial inference that Gold is not Hardgrep because Silver is. Accordingly, touch the gold statue.